Hair salon has 30 gal. water tank and 2 hair sinks, utility sink and bathroom sink it keeps loosing hot water .it seems to be more frequently now, it used to be when it was really busy times, now its not as busy and it will get cold by the end of the night, also when we use the both sinks at the same time , one will go cold. could there be a leak or is it the tank!

Heather, March 2008

Presumably the 30 gallon tank you mention is the hot water storage cylinder (copper). A 30.8 gal cylinder is 530 mm in diameter and 1130 mm high (including a layer of factory applied insulation).
(1) If the cylinder doesn't have insulation on it already, get a lagging jacket!
(2) How is your water being heated? - (a) electric immersion heater only (b) indirect cylinder with coil connected to heating system or (a) and (b).
(3) Hair dressing - typical usage is 10 litres (hot water) per shampoo.
(4) Recommended storage is 30 Litres per person for a domestic situation with one bath and 45 L /person if there is more than one bath.
Storage volume and heat input have to be considered together. If you have a small storage volume, it means that cold water has to be heated to say around 65C, in a much shorter time. this requires more kilowatts of heat input - i.e. a bigger boiler.

JD, March 2008